The distance between the number of people who have a common mental disorder and the number who receive care for it is usually called the treatment gap, and it is widest in low- and middle-income countries and in rural districts within them (Kohn et al., 2004). Psychological treatments with good evidence exist, but they were developed for delivery by psychologists and psychiatrists, who are few and concentrated in cities. The response that has gained most ground is task sharing, in which people without specialist training deliver defined elements of care under supervision (Patel et al., 2018).

Community health workers are an obvious workforce for this purpose. They live in the communities they serve, they already visit homes for maternal and child health or infectious disease programmes, and they are trusted. They are also busy, often modestly schooled and seldom trained in mental health. A treatment has to be reshaped before they can deliver it, and the reshaping is a technical task with its own methods.

This article sets out a procedure for that task. It is written for programme managers, trainers and researchers who have chosen, or been asked, to introduce a brief psychological intervention through community health workers in a rural area. The procedure draws on published adaptation frameworks and on the methods reported by trial teams. It is a proposal and has not been applied or evaluated in this article.

Evidence that non-specialists can deliver effective psychological care has accumulated over two decades. In rural Uganda, group interpersonal psychotherapy led by trained local facilitators reduced depression (Bolton et al., 2003). In rural Pakistan, the Thinking Healthy Programme, a cognitive behavioural approach woven into the routine home visits of community health workers, improved recovery from perinatal depression (Rahman et al., 2008). In Goa, lay health counsellors working within a collaborative stepped-care model improved outcomes for common mental disorders in public primary care (Patel et al., 2010), and a later trial found that a brief behavioural activation treatment delivered by lay counsellors was effective for severe depression (Patel et al., 2017). In Zimbabwe, problem-solving therapy given by lay health workers on the Friendship Bench reduced symptoms of common mental disorders (Chibanda et al., 2016). A Cochrane review concluded that non-specialist health workers can improve outcomes for depression and anxiety, while judging much of the evidence to be of low or moderate certainty (van Ginneken et al., 2013).

These programmes have features in common. A review of psychological treatments tested in low- and middle-income countries found that most were short, relied on a small set of elements such as behavioural activation, problem solving and interpersonal skills, and were delivered with structured supervision (Singla et al., 2017). The World Health Organization built its Problem Management Plus programme on the same reasoning, combining stress management, problem solving, behavioural activation and strengthening of social support in a format for lay helpers (Dawson et al., 2015). On cultural adaptation, a systematic review found that most adaptations concerned language, context and the person delivering the treatment, and that the core content of the parent therapies was generally retained (Chowdhary et al., 2014).

The procedure has five stages, shown with their outputs in Figure 1. It follows the general logic of guidance on complex interventions, which advises that development, piloting and evaluation be treated as distinct phases and that the reasoning behind an intervention be made explicit (Craig et al., 2008).

Several features of rural work cut across the stages. Home visiting brings care to people who could not travel, but homes are seldom private, and a session held within earshot of in-laws or neighbours is a different thing from one held in a clinic room. Teams should decide where sessions can take place and how the worker will explain the visits to others in the household. In a small community the worker is likely to know the client socially, which builds trust and also raises the stakes for confidentiality. Training has to address this directly, with clear rules on what may be shared and with whom.

Workload is a second concern. Community health workers are asked to carry many programmes, and adding a psychological intervention without removing other duties or adjusting incentives invites superficial delivery and burnout. The scope agreed in stage 1 should be negotiated with the health authority that employs the workers. Finally, referral routes are thin. A protocol for responding to suicide risk or severe illness is only as good as the service at the other end of it, and the team should confirm, before training begins, who will receive referrals, how the person will get there and what the worker should do in the meantime.

The procedure has been put together from frameworks and from accounts of programmes that worked; it has not itself been tested, and accounts of success are a selective source. It is not known whether following these stages produces better interventions than a quicker, less formal adaptation, nor which stages contribute most. The balance between fidelity to a parent treatment and fit to local conditions remains a matter of judgement, and the procedure offers a way to document that judgement without resolving it.

Evaluation should proceed in steps. Early studies would examine implementation outcomes such as acceptability, feasibility, fidelity and reach, which are distinct from clinical outcomes and need their own measures (Proctor et al., 2011). A controlled trial would then be required to establish effectiveness, using outcome measures validated in the local language. Comparative work across sites, with adaptation logs published alongside results, would show over time which adaptations are needed everywhere and which are specific to a place.

Brief psychological treatments can be delivered by community health workers, and the trials that show this also show that careful preparation lies behind each success. The five-stage procedure described here orders that preparation: choose and scope the treatment, learn from the community, simplify and adapt the content, build training and supervision, and pilot with honest documentation. It is offered as a working method for teams in rural settings and as a proposal to be tested, revised and improved by those who use it.

To be declared by the author(s) before publication.

To be declared by the author(s) before publication.